Abstract
The flow around a rotating disk in a cylindrical casing is investigated by the numerical and experimental methods. The radius of the disk is shorter than the inner radius of the casing, as well as the thickness of the disk is smaller than the length of the casing. Therefore, the flow field has a radial gap in addition to a narrow axial gap. The rotation of the disk in a cylindrical casing generates the flow with bead-like and sickle-like vortex, and spiral rolls is confirmed by the numerical calculation between the disk and the stationary walls. We investigated by visualization the generation and the transition process of such a flow that depended on the Reynolds number. As a result, the critical Reynolds numbers at which the flow transition appears is examined.
